midterm #3 practice test #1 - arizona state universitychemistry 234, midterm #3 practice test #1 - 4...

Ian R. Gould

PRINTED FIRST NAME

Person on your LEFT (or Aisle)

H He

Li Be B C N O F Ne

Na Mg Al Si P S Cl Ar

K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr

Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe

Cs Ba Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn

CHEM 234

PRINTED LAST NAME

H/H ~1.0

Eclipsing

H/Me ~1.4

Me/Me ~2.6

Me/Me ~0.9

Et/Me ~0.95

i-Pr/Me ~1.1

t-Bu/Me ~2.7

Gauche

Me/Et ~2.9

Interaction Energies, kcal/mol

ASU ID or Posting ID

Person on your RIGHT (or Aisle)

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C NR2

RC CRR2C CR2

Aromatic

CR OHO

C X

R NH2R OH

aminealcohol

3Y > 2Y > 1Y

020406080100120140160180200220

–H2C X

–H2C NR2

–OCH2–

01234567891011

C CHC HO

CR OHO

Aromatic Ar HAlkylmainly 8 - 6.5

C CH2

C CH3

O

3Y > 2Y > 1YAlkyl–OCH2–

CO

(δ, ppm)

variable and condition dependent, ca. 2 - 6 δ

R C N

O H C N

CN

CC

H

C ON H

C H

C N

O

HCO

CH

C CH

COR

ON H

C H

CO

O H

C O HO

CNR2

O

3000–3100

2850–2960

3300

broad ~3300

broad with spikes ~3300

2200

broad ~30001710

2200

1650

2720–28202 peaks

1735

1600–1660

1680

range of valuesbroad peak

small range usuallystrong

1600

CH

CH

C CHH

CH

CH

CH

CH

H

H

H

H

Approximate Coupling Constants, J (Hz), for

1H NMR Spectra

~7

~10

~2

~15~2

~8

Infrared Correlation Chart

NMR Correlation Charts

3000 200025003500 1500(cm-1)

THIS IS A CHM 234PRACTICE EXAM

MIDTERM #3PRACTICE TEST #1

the exam cover sheets look kind of like this

CHEMISTRY 234, MIDTERM #3 PRACTICE TEST #1 - 2 - NAMEQuestion 1 Give the IUPAC name for the following compounds. Be sure to use cis/trans, E/Z or R/S where appropriate.

O

H

OH

Question 2 Rank in order of increasing equilibrium constant for formation of an acetal with a brief explanation. Draw the expected acetal for one of the reactions (only), it does not matter which one.

H

O MeOH

H+ (cat.)A

O MeOH

H+ (cat.)B

H

O MeOH

H+ (cat.)C

F F

Question 3 Give the alkyl bromide and the carbonyl compound you would use to synthesize the following alkene in a Wittig synthesis and show all steps and reagents/conditions

Ph

Question 4 For each reactiona) Provide the missing reagents/conditions or major organic products as appropriate, pay attention to stereochemistry including racemic mixtures unless specifiedb) Unless otherwise indicated.....State whether the OVERALL reaction is Addition, Elimination, Substitution or RearrangementState whether the reaction is oxidation, reduction or neitherBriefly explain whether the a solution of the product would be optically active or not

b)

a)

CHEMISTRY 234, MIDTERM #3 PRACTICE TEST #1 - 3 - NAME

d)

c)

e)

O

Zn(Hg)

HCl, H2O

H

H

O O H3O+

O

OCO/HClAlCl3

H

1 Equiv. (CH3)2NH

HCl (cat.)

O

H

O

ignore stereochemistry/optical activityignore oxidation/reductionignore addition/elimination etc

HO

OH

Na2Cr2O7/H2SO4

ignore stereochemistry/optical activityignore addition/elimination etc.

ignore stereochemistry/optical activityignore oxidation/reduction etc.

ignore stereochemistry/optical activityignore oxidation/reductionignore addition/elimination etc

CHEMISTRY 234, MIDTERM #3 PRACTICE TEST #1- 4 - NAME

Question 5 Draw the complete arrow pushing mechanism for the following reaction. Indicate the Lewis acid/base at each step, and if they are also Brønsted acids bases. Add non-bonding electrons as necessary. Draw the ALL important resonance structure of the intermediates

O NH

TsOH (cat.)

NH3

Question 6 Rank the following in terms of increasing rate of reaction with PhMgBr. Give a BRIEF explanation and NAME the three functional groups

O

––– ––– –––< <B C

O

O

H

O

A


CH3CO2H

Br

NO2

a)

Question 7 Show how you would make the target molecules from the provided starting structures. Show all intermediate structures, do not show any mechanisms

b) OHO

O


Question 1 Give the IUPAC name for the following compound. Be sure to use cis/trans, E/Z or R/S where appropriate.

START OF PRACTICE TEST #2

O

H

OH

Question 2 Rank the following in terms of increasing rate of electrophilic aromatic substitution, e.g., reaction with HNO3/H2SO4. Give a BRIEF explanation

OO

––– ––– –––< <A

O

O

OO

B

OO O

C

OO O

H3O+

O

N

Question 3 Give the product of complet acid catalyzed hydrolysis of the following structure


Question 4 For each reactiona) Provide the missing reagents/conditions or major organic products as appropriate, pay attention to stereochemistry including racemic mixtures unless specified

b)

a)

d)

c)

e)

C N

O

O NMe2

1.

2. Zn/Hg/HCl/H2O

Cl

OAlCl3

MeO

S S PhCH2 CH3

O

H H

CH3OH

CH3O–

H

O


Question 5 Give a full curved arrow-pushing mechanism for the following reactions, show where every proton goes to and comes from (no +H+/-H+) and indicate the Lewis and Bronsted acids/bases at each intermolecular step, include important resonance contributors for all intermediates, give the number of steps in your mechanism.

OO

O

OHHOHCl/H2O

OH ONaOH/H2O

a)

b)


Question 6. Show how you would synthesize the target componds on the right from the starting compounds on the left. Show reagents and conditions, and the structures of important intermediate compounds. Do not show any (arrow pushing) mechanisms.

HO

a)

a)

O

OH

OH




Question 2. Give a complete curved arrow pushing mechanism, and...1) Indicate the Lewis acid/Lewis base (LA, LB) at each step as appropriate, and whether they are also Brønsted acids/bases (LA/BA, LB,BB), show where every proton comes from and goes to (no +H+/-H+)2) GIVE THE NUMBER OF STEPS IN YOUR MECHANISM

OOH

HClOO

HO

O OOH

Question 3 For each reaction1) Provide the missing reagents/conditions or major organic products as appropriate

b)

a)


c)

d)

e)H

O

O

1 Equiv.HO OH

ignore stereochemistryTsOH (cat.)

O

O

OMgBr

Ph

H3O+

N

Ph

H3O+

HN CO/HCl

AlCl3Br

Br2. BuLi3. O

1. PPh3


Question 4 Rank the following in terms of increasing frequency of carbonyl stretching vibration in an IR spectrum. To solve this problem you will ened to draw minor resonance contributors and remember that stronger bonds vibrate with higher frequency)

H3C H

O

H3C

O

H3C NMe2

O

––– ––– –––< <CA B

Question 5 Give the product of the following reaction. Remember that D represents deuterium, an isotope of hydrogen, that is used to keep track of where hydrogen atoms go in chemical reactions. We did not cover this reaction class, but you should be able to work it out based on what you know about the mechanisms of these reduction reactions

CH3H3CCN 1. LiAlH4

2. D3O+

H


CO2H

SO3HBr

b)

O

BrHO

OH

a)

Question 6. Show how you would synthesize the target componds on the right from the starting compounds on the left. Show reagents and conditions, and the structures of important intermediate compounds. Do not show any (arrow pushing) mechanisms.


O

O

H3O+

a)HO

HO+CO

H

H


N

NOH

NH

HN

NOH

OH

uracilcytosinetautomer

cytosine is one of the pyrimidine bases in DNA, it can be converted into uracil. if this happens this can be a damage mechanism that could lead to mutation. Assume that this reaction occurs via the usual acid catalyzed mechanisms that we study in class, give a mechanism for formation of uracil from teh provided tautomer of cytosine

H3O+b)




O

H

O

Question 2 Rank the following in order of increasing equilibrium constant for formation of a hydrate. Give a BRIEF explanation

––– ––– –––< <A B C

O

H3CO

OO

O2N

Question 3. Rank in order of increasing rate of reaction with –CN, give a BRIEF explanation

BA

<

C

<

O

O

O

F F

O

(fastest) (slowest)

Question 4. For each reaction.1) Provide the missing reagents/conditions or major organic products as appropriate2) Pay attention to stereochemistry including racemic mixtures unless specified

b)

a)


c)

d)

e)

OH+ cat.

(CH3)2NH

Br2 / FeBr

F3C

KOH/heat

OBr N2H4

NH2

OHCl (cat.)

H

O

OHO H3O+


Question 5. Show how you would synthesize the target compound on the right from the starting compound on the left. Show reagents and conditions, and the structures of important intermediate compounds. Do not show any (arrow pushing) mechanisms.

a)

NH2

Br

Cl

O

O

HHO

HPh

Nb)


O

O

b)

HO OHH3O+ O

+


a)

O

H3O+

O


––– –––

Question 7 Rank in order of increasing rate of reaction with a Grignard reagent, giove a brief explanation in terms of nucleophiles and electrophile stregth and tthe factors that control these in this context.

––– –––< <<

F3C H

O

H H

O

H3C CH3

O

H3C H

O

DCBA

Question 8. Rank in order of increasing rate of electrophilic aromatic substitution at the carbons indicated by the arrows. Give a BRIEF explanation.

B

C

A

slowest fastest

< <

CN

NH

CH3

D

<

midterm #3 practice test #1 - arizona state universitychemistry 234, midterm #3 practice test #1 - 4...

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